Sub-Guide to Rarely Branched (mostly acrocarpous) Mosses

Group A1 - Shoots flat or angular, not round (Skeleton)

Shoots flattened; leaves 2-ranked (lying in one plane).

Leaves distichous (attached in two rows on opposite sides of the stem).

Leaves cleft at anterior edge and clasping posterior edge of next leaf; WS

Leaves conduplicate, crowded, and progressively larger; the "Sword " moss; WS*

Leaves flat, decurrent and confluent; protonemata luminous; "Goblin Gold"; WS*

Leaves needle-like; a roughened subula from a sheathing, shiny-white base; WS

Leaves complanate (attached all around the stem, but twisted into one plane).

Leaves with a long, single costa; cells smooth.

Leaves distant on stoloniferous shoots and bordered by linear cells; WS

Leaves crowded, unbordered and +undulate; capsules plicate (dry); E

Leaves ecostate; cells short and pleuripapillose; GC

Shoots triangular ; leaves 3-ranked .

Plants minute with immersed capsules; leaves broadly ovate with recurved apiculi; WS

Plants larger with exserted capsules; leaves ovate lanceolate, squarrose and decurrent.

Cells strongly papillose; plants on dry soils; CA

Cells smooth; in calcareous wetlands.

Capsules with well-defined neck; endostome longer than exostome; N

Capsules short & black (golf clubs); endostome reduced to lacking; N

Shoots angular ; leaves 4-5 ranked .

Stems densely tomentose; leaves squarrose recurved; in calcareous wetlands; N

Stems smooth; leaves crowded and appressed; on soil near rocks; A/A

Group A2 - Shoots julaceous when wet (Skeleton)

Stems red

Stems freely forked; plants whitish; capsule necks extremely long; A/A

Stems sparsely forked; capsule necks mostly short to moderate in length.

Cells long (~ 8:1); N*

Cells intermediate (~4:1).

Upper leaves abruptly acuminate; capsules erect; peristome single; NW

Upper leaves apiculate; capsules pendent; peristome double; WS

Stems green

Cells unipapillose and +stellate; leaves concave-cucullate; A/A.

Cells +prorulose; leaves 5-ranked and serrate; plants bluish-white; A/A

Cells smooth; leaves radially arranged.

Leaves serrulate and unbordered; immersed capsules: E

Leaves entire and bordered with longer cells; exserted capsules; WS

Group A3 - Stems distinctly tomentose (Skeleton)

Stems covered with pigmented (reddish to brownish) rhizoidal tomentum to near apex.

Leaves squarrose-recurved and heart shaped; fens; N

Leaves ovate to broadly elliptical.

Rhizoidal initials in longitudinal rows; endostome fused into a dome; N

Rhizoidal initials not in rows; endostome segments free; N*

Leaves oblong- lanceolate to oblong-lingulate.

Cells pleuripapillose; terminal cell long and smooth; brood bodies axillary; N*

Cells unipapillose; terminal cell papillose; brood bodies terminal; WS

Cells smooth; leaves broadly lingulate; a copper -sulfur moss; WS (E)

Leaves narrowly lanceolate from an ovate, plicate base; WC, NW

Leaves lanceolate to subulate -setaceous; WS

Stems covered with white-wooly tomentum.

Leaves with green sheets (lamellae) on their surface; bogs; N*

Leaves lacking lamellae; WS

Group A4 - Stems red (Skeleton)

Plants julaceous .

Stems freely forked; leaves with distinct, +reflexed point ; cells in oblique rows; A/A

Stems occasionally forked; leaves ovate to ovate-lanceolate and concave.

Leaves broadly obtuse to acute; costa ending subpercurrent; cells ~8:1; N*

Leaves abruptly acuminate; costa percurrent; cells ~4:1; NW

Leaves obtuse to acute; costa percurrent to excurrent; cells ~4:1; WS

Plants with stems covered with pigmented (reddish to brownish) tomentum .

Leaf cells >3:1; WS

Leaf cells <2:1.

Rhizoidal initials in longitudinal rows; endostome fused into a dome; N

Rhizoidal initials not in rows; endostome segments free; N*

Plants neither julaceous nor tomentose.

Leaves bordered by elongated cells.

Leaves distinctly toothed.

Cells strongly bulging; AK

Cells smooth.

Cells very large (to 150x50µ); leaves rugose; WC, NW, CO

Cells smaller (up to 50µ); leaves plane; WS

Leaves entire.

Leaves +dimorphic (+distichous lateral leaves and smaller dorsal leaves); WC

Leaves of one kind; WS

Leaves not bordered.

Leaves serrulate +throughout; cells prorulose; WS

Leaves +serrulate near the apex; cells smooth.

Leaves subulate; alar cells inflated, thick-walled and reddish; N*

Leaves not subulate; alar cells +undifferentiated; WS

Group A5 - Leaves squarrose-recurved (Skeleton)

Leaves squarrose-recurved when dry (or wet).

Leaves 5-ranked and folded to appear heart shaped; stems densely tomentose; fens; N

Leaves squarrose-recurved only when wet (+appressed when dry).

Leaves 3-ranked, long-decurrent and with papillose-crenulate margins; CA

Leaves subulate -setaceous from a sheathing base; disturbed soil; N

Leaves with wavy margins; hyaline basal and marginal cells; on dry limestone; SE

Leaves distinctly toothed in upper half; cells papillose.

Leaf lamina +bistratose; stem hyalodermis present; peristome lacking; SW

Leaf lamina unistratose; stem hyalodermis lacking; peristome present; SE

Leaves lacking the above unique characteristics.

Cell walls irregularly thickened; cell lumens stellate; A/A

Cell walls of uniform width; cell lumens +rounded.

Cells intermediate in length; WS

Cells short.

Leaves +bordered by longer, or shorter and thick -walled cells; 1*; WS

Leaves unbordered; 2* ; WS

A6 - Leaves falcate-secund (Skeleton)

Plants blackish; leaves multistratose; capsules valvate ; on rocks; NW

Plants grayish; costa >1/2 leaf breadth with 3(4) cell layers; green striations on dorsal surface of leaves; N*

Plants green; leaves unistratose and lacking striations; costa usually <1/5 leaf breadth.

Alar cells clearly differentiated; plants large , mostly >1cm.

Alar cells pigmented; capsules rarely strumose; various habitats; 2*; WS

Alar cells pale; capsules strumose ; on alpine rocks; 0*; A/A

Alar cells +undifferentiated; plants small, mostly <1cm; WS

Group A7 - Leaves subulate / setaceous (8:1 or greater) (Skeleton)

Setae curved ; capsules laterally emergent and operculate; FL and GA

Setae straight ; capsules immersed and cleistocarpous.

Capsules pyriform with a conspicuous, stomatose neck; spores small; WS

Capsules globose to ovoid , lacking a distinct neck.

Calyptrae mitrate or cucullate; spores numerous and small; WS

Calyptrae rudimentary; spores few and large (>100µ); E

Plants larger with exserted capsules growing on various substrates.

Leaves squarrose - recurved (wet); subula roughened throughout by cell ends; N

Leaves with bases distinctly incurved to expanded and clasping.

Cells intermediate in length and prorulose/papillose; upper cells + bistratose; WS

Cells intermediate in length and smooth.

Capsules with distinct , very long necks; WS

Capsules lacking a distinct neck.

Plants minute; peristome double with entire, papillose teeth; NT

Plants larger ; peristome single with forked teeth.

Teeth divided to base, round and papillose; WS

Teeth divided to mid - point , flat and pitted - striolate ; WS

Cells short and smooth.

Upper cells + bistratose; capsules inclined, asymmetric and strumose; WS

Upper cells unistratose; capsules erect , symmetric and cylindrical; SW

Leaves with a broad , single costa (>1/3 the leaf width).

Alar cells inflated and hyaline or colored (brownish to reddish).

Costa 3(4) cell layers thick (middle layer green; external layers hyaline); N*

Costa lacking the above unique characters.

Inner basal cells pale, enlarged and extending up along the costa; N*

Inner basal cells little differentiated; WS

Alar cells +undifferentiated.

Costa of 3(4) cell layers (middle layer green; external layers hyaline); E

Costa lacking the above unique characters; reddish, axillary hairs common; WS

Leaves lacking the above unique characteristics.

Alar cells distinctly differentiated .

Capsules curved and strumose (goiter-like swellings); on rocks; A/A

Capsules obovoid to pyriform; on rocks .

Capsules ribbed (dry); peristome teeth wide-flaring, +split and striolate; N

Capsules smooth (dry); peristome teeth erect, +entire and papillose; N*

Capsules lacking any of the above unique characters; substrates various .

Cells with cuticular ridges; peristome teeth +entire and papillose; N*

Cells smooth; peristome teeth forked and pitted-striolate below; WS

Alar cells + undifferentiated.

Stems tomentose & red; leaves serrate above & recurved below; WC, NW

Stems tomentose at base; leaf margins doubly serrate; archegonia +basal; CP

Stems lacking tomemtum & green.

Cells intermediate to long; peristome teeth usually present.

Plants small (<2mm); leaves little altered (dry); on rocks; WS

Plants larger (>5mm); leaves twisted (dry); on wood; SA, WC

Cells short ; annulus compound; peristome teeth mere stubs; WS*

Group A8 - Leaves dimorphic (Skeleton)

Leaves costate , 4-ranked and bordered ; dorsal leaves smaller; stems red ; cells smooth; WC

Leaves ecostate , 4-ranked and complanate ; ventral leaves smaller; cells pleuripapillose; GC

Group A9 - Leaves with hair-points or awns (Skeleton)

Leaves with lamellae on the upper end of the costa; WS

Leaves with filaments on the upper end of the costa.

Leaves "fleshy " with inrolled margins; filaments on very broad costa; WC

Leaves thin with reflexed to revolute margins; filaments on narrow costa; W

Leaves lacking lamellae or filaments

Leaves with a revolute margin; cells pleuripapillose; WS

Leaves with reflexed tips; cells with single blunt papillae; WS*

Leaves with plane margins and tips; cells smooth.

Capsules exserted and peristomate; calyptrae cucullate; NW

Capsules +emergent and operculate; calyptrae persistent, 4-angled and split; E

Capsules immersed and cleistocarpous; spores few and large (>100µ); TX

Plants growing on dung , animal remains, or other highly nitrogenous materials; the "dung mosses ".

Hypophysis greatly differentiated and colored; peristome teeth chambered; N, CP, SA

Hypophysis narrowly pyriform and +urn-colored; peristome teeth not chambered; N

Hypophysis lacking; cleistocarpous; A/A

Plants lacking any of the above unique characteristics.

Leaves "fleshy" from crowded lamellae covering a very broad costa; WS

Leaves with a broad (1/3 - 1/2 leaf width) single costa; WS

Leaves ecostate.

Cells +isodiametric throughout with conspicuous primordial utricles; TX

Cells short rhomboidal (>3:1) above; TX, OK

Leaves with distinct border.

Cells short (+isodiametric); pleuripapillose or smooth; WS

Cells intermediate in length; smooth.

Capsules pendent and pyriform; WS

Capsules erect and +cylindric; GC, SW, SA

Leaves with large, lax and hyaline basal cells contrasting with dense upper cells.

Basal cells pale with brown, thickened cross walls; calyptrae campanulate; WS

Basal cells thin -walled and non-pigmented throughout; calyptrae cucullate.

Peristome of 32 twisted teeth on a high basal membrane; WS

Peristome of 32 +erect teeth on a low basal membrane; WS

Leaves lacking the above unique characteristics.

Leaf cells distinctly papillose; marginal cells greener ; on mountain rocks and soil; WC, SW

Leaf cells smooth or indistinctly ornamented.

Plants in tufts on tree trunks and branches (rarely on rocks); diplolepideous.

Leaves crisped when dry; basal cells yellow, thick -walled and in diagonal rows; WC

Leaves not crisped when dry; basal cells undifferentiated; WS*

Plants in tufts, cushions and mats on rocks; haplolepideous.

Calyptrae large, campanulate, plicate and lacerate at base.

Leaves ovate to obovate; WS (W)

Leaves ovate-lanceolate and biplicate; N*

Calyptrae small, cucullate or mitrate.

Capsules systylious; calyptrae short; in wetter habitats; WS

Capsules not systylious; calyptrae reaching operculum; in dryer habitats; WS

Plants on soil primarily.

Cells intermediate in length; capsules pendent and pyriform; WS

Cells short (+isodiametric); capsules mostly erect and cylindrical; WS

Group A10 - Leaves with lamellae, ridges, or filaments (Skeleton)

Leaves with green , sheet-like lamellae .

Leaves with a very broad costa covered by >20 lamellae.

Leaves mostly bistratose; caducous awns ; peristome lacking; A/A

Leaves mostly unistratose; peristome present.

Lamellar apical cells papillose; capsules +terete.

Leaves subtubulose; lamellar apical cells elliptic-pyriform; WS

Leaves oblong lanceolate; lamellar apical cells +rounded; WS

Lamellar apical cells smooth or ridged; capsules sharply 4-5 angled; WS

Leaves with a narrow costa having <20 lamellae.

Lamellae on both surfaces of leaves; leaves unbordered; 5-15 lamina; WC, NW

Lamellae restricted to the upper surface of leaves.

Leaves with awns; 2-4 lamellae; plants +bulbiform; WS

Leaves with cilia at leaf shoulder; 5-15 lamellae; WA, BC, AK

Leaves bordered by hyaline, elongate cells; 2-8 lamellae; WS

Leaves bordered by hyaline, short , diagonally oriented cells; 5-15 lamellae; A/A.

Leaves with ridge -like lamellae on the back (dorsal side) of the costa.

Stems tomentose (wooly; white to rusty brown); alar cells hyaline and yellow -brown; WS

Stems smooth ; alar cells not pigmented.

Costa broad (>1/3 leaf width); ridges weak (1-2 cells); cells short-rectangular; WS

Costa narrow (<1/3 leaf width); ridges strong (>6 cells); cells rounded-oblate; N

Leaves with green , branched filaments .

Leaves fleshy : filaments on lamina and costa, but covered by inrolled leaf margins; WS*

Leaves thin; filaments on costa only; leaf margins reflexed to revolute; W

Leaves with fine, white , threadlike filaments in a tangled, cobwebby weft ; N*

Group A11 - Leaves undulate (Skeleton)

Leaves complanate (attached all around the stem but twisted into one plane); E

Leaves with lamellae on the costa; WS

Leaves with hyaline, marginal wedges broadest at the base; WS

Leaves lacking any of the above unique characteristics; N

Group A12 - Leaves involute (Skeleton)

Leaf margins involute wet or dry.

Leaf margins infolded/inflexed over photosynthetic lamellae or filaments.

Leaves with green, sheet-like lamellae; WS

Leaves with green, branched filaments; WS*

Leaf margins inrolled over laminae lacking lamellae or filaments.

Leaf cells papillose.

Capsules exserted and operculate; WS

Capsules immersed to emergent, cleistocarpous; E

Leaf cells smooth; laminae +bistratose.

Leaf margins spirally inrolled above a sheathing base; AK

Leaf margins not spirally inrolled; WS

Leaf margins involute when dry ; plane to erect when wet; cells bulging on upper surface.

Leaves +toothed above; costa with two stereid bands; peristome lacking; E

Leaves + entire; costa with one stereid band; peristome present; FL, GA

Group A13 - Leaves +all costa (Skeleton)

Leaves channeled and subtubulose; E

Leaves flat on the upper side; FL, LA.

Group A14 - Leaves with a broad, single costa (Skeleton)

Leaves bristle-like (setaceous) or with distinct hair-points.

Leaves with a costa of 3(4) cell layers (middle layer green; external layers hyaline); N*

Alar cells distinctly inflated; costal stereid cells & brood bodies lacking; N*

Alar cells weakly differentiated; costal stereid cells & brood leaves common; E

Leaves crowded at stem tips; reddish, axillary hairs common; WS

Leaves lacking any of the above unique characteristics

Leaves with strongly differentiated alar cells (inflated and hyaline)

Inner basal cells pale, enlarged and extending up along the costa; N*

Inner basal cells little differentiated; WS

Leaves with alar cells little differentiated.

Leaves >3mm; upper cells elongate; MO

Leaves <3mm; upper cells rectangular to linear; WS

Leaves oblong -lanceolate ; capsules elongate, curved and with a conspicuous neck.

Upper leaf cells oblong-hexagonal, thin-walled & lax; N

Upper leaf cells short rectangular, thick-walled & not lax; N

Reminder - The costa in Groups A15 through A19 is long and single.

Group A15 - Leaves with bases distinctly incurved to expanded and clasping (Skeleton)

Leaves squarrose - recurved.

Leaves subulate / setaceous; subula roughened throughout by cell ends; N

Leaves ovate- lanceolate, strongly apiculate and with apical teeth; SW

Leaves subulate / setaceous (needle or bristle-like).

Cells intermediate in length and prorulose/papillose ; upper cells + bistratose ; WS

Cells intermediate in length and smooth.

Capsules with distinct, very long necks; WS

Capsules lacking a distinct neck.

Plants minute; peristome double with entire, papillose teeth; NT

Plants larger ; peristome single with forked teeth.

Teeth divided to base, round and papillose; WS

Teeth divided to mid - point , flat and pitted - striolate; WS

Cells short and smooth

Upper cells + bistratose; capsules inclined , asymmetric and strumose; WS

Upper cells unistratose ; capsules erect , symmetric and cylindrical; SW

Leaves with lamellae or ridges on their laminae or costa.

Leaves with a very broad costa covered by >20 lamellae.

Leaves mostly bistratose; caducous awns ; peristome lacking; A/A

Leaves mostly unistratose; peristome present.

Lamellar apical cells papillose; capsules +terete.

Leaves subtubulose; lamellar apical cells elliptic-pyriform; WS

Leaves oblong lanceolate; lamellar apical cells +rounded; WS

Lamellar apical cells smooth or ridged; capsules sharply 4-5 angled; WS

Leaves with a narrow costa having 5-15 lamellae.

Lamellae on both surfaces of leaves; leaves unbordered; WC, NW

Lamellae on upper surface of leaves only; cilia at leaf shoulder; WA, BC, AK

Leaves bistratose with spirally inrolled margins; AK

Group A16 - Leaves with long decurrencies (Skeleton)

Plants dendroid; stem leaves bordered with long, marginal, right-angled teeth; WC, NW

Plants not dendroid.

Shoots angular in cross-section; leaves squarrose recurved; cells short and papillose .

Leaves 3 -ranked ; stems smooth; CA

Leaves 5 -ranked ; stems densely tomentose ; calcareous wetlands; N

Shoots terete (round in cross-section); capsules pyriform or pendulous.

Leaves distinctly toothed +throughout.

Marginal teeth paired; sterile stems +erect and round; WS

Marginal teeth single; sterile stems prostrate and complanate; WS

Leaves entire to +serrulate or +toothed at apex.

Leaves predominantly broader near the middle; capsules pendent.

Leaves commonly bordered; median cells <4:1; WS

Leaves not bordered; median cells >4:1; WS

Leaves predominantly broader at the base; setae very long; capsules +inclined; N

Group A17 - Leaves with a distinct group of hyaline cells (Skeleton)

Hyaline cells at apex of leaves; plants whitish .

Stems often forked or branched, especially at stem apices.

Cells papillose (simple and forked); capsules immersed; peristome lacking; WS

Cells smooth; capsules exserted with extremely long necks; peristomate; A/A

Stems rarely branched; leaves apiculate; capsules pendent; cells smooth; WS

Hyaline cells as marginal wedges broadest at the base of leaves.

Leaves squarrose-recurved and serrulate above; upper cells pleuripapillose; S

Leaves spreading and crenulate to entire.

Leaves lingulate with rounded-obtuse apices; upper cells bulging; GC

Leaves acute to acuminate; upper cells pleuripapillose; WS

Hyaline cells in abruptly differentiated, +oval "windows " (cancellinae) in the lower 1/3 of leaves.

Leaves with linear, intramarginal cells; calyptrae persistent , clasping and split; FL

Leaves lacking linear, intramarginal cells; calyptrae deciduous and cucullate.

Leaf margins revolute; peristome of 32 twisted teeth; 1*; WS

Leaf margins plane; peristome of 16 straight teeth; 2* ; E(GC)

Hyaline, inflated and thin-walled cells across the lower 1/3 of leaves.^#

Leaves abruptly serrate at the shoulder and whorled at branch points; 2*; WS

Leaves toothed above; 2*

Upper leaf cells densely pleuripapillose; capsules smooth; 2*

Older leaves brick-red; stems lacking a hyalodermis; WS

Older leaves brownish-green ; stems with a hyalodermis; BC

Upper leaf cells smooth; capsules 8-ribbed (dry); E

Leaves bistratose along margins, in longitudinal rows or +throughout.

Leaf margins erect/involute; calyptrae plicate; peristome 16 +coherent teeth; 2*; WS

Leaves revolute at least below; 1*.

Leaves +rounded with short to long awns; cells 10-13 µ; peristome present.

Peristome of 32 twisted teeth on a high basal membrane; WS

Peristome of 32 +erect teeth on a low basal membrane; WS

Leaves +acute; cells 15-20 µ; peristome none or rudimentary; WS

Leaves lacking any of the above unique characteristics.

Cross walls of basal cells thick and brown; calyptrae long campanulate; 1* ; WS

Cross walls of normal thickness; calyptrae cucullate.

Stems with a hyalodermis; papillae usually bifid; 2* .

Stems with a central strand (small cells); NW, WC, GC

Stems lacking a central strand; WS

Stems lacking a hyalodermis; papillae usually C-shaped; 1*.

Peristome of 32 twisted teeth on a high basal membrane; WS

Peristome of 32 +erect teeth on a low basal membrane; WS

Group A18 - Leaves with a distinct marginal border (Skeleton)

Leaves ciliate at the margins.

Plants primarily protonemata; capsules inclined, ovoid and ventricose; WS*

Plants leafy; capsules not differentiated as above.

Leaves with 4-9 lamellae on costa; cilia at leaf shoulder; WA, BC, AK

Leaves lacking lamellae; cilia at leaf base; WA, AK

Leaves with a border of elongate cells contrasting with shorter medial cells.

Plants dendroid; stem leaves bordered with long, marginal, right-angled teeth; WC, NW

Plants erect, rosulate -foliate and large; from horizontal, underground stems; WS

Plants strongly flattened; leaves twisted into one plane (complanate); WS

Plants with red stems.

Stems tomentose.

Rhizoidal initials in longitudinal rows; endostome fused into a dome; N

Rhizoidal initials not in rows; endostome segments free; N*

Stems smooth.

Leaves +rugose; cells thin-walled and very large (to 150x50µ); WC, NW, CO

Leaves 4 -ranked and dimorphic (dorsal leaves smaller); WC

Leaves lacking the above unique characteristics; cells strongly bulging; AK

Plants lacking the above unique characteristics.

Leaves with lamellae on the costa; WS

Leaves with abruptly differentiated cancellinae (hyaline basal cells); E (GC)

Leaves with paired teeth on margins; WS

Leaves with distinct single teeth or serrulations on margins.

Leaf cells >3:1.

Leaves rounded-obtuse and apiculate; upper cells in oblique rows; N*

Leaves acute to awned; cells not in oblique rows.

Capsules pendent and pyriform; WS

Capsules erect and +cylindric; GC, SW, SA

Leaf cells <2:1; WS

Leaves with entire margins.

Leaf cells >3:1.

Capsules pendent and pyriform; WS

Capsules erect.

Leaves rounded-obtuse; upper cells in oblique rows; N*

Leaves broadly acute; cells not in oblique rows; WS

Leaf cells 1-2:1; A/A

Leaves bordered by hyaline , diagonally oriented cells; 5-15 lamellae on costa; A/A.

Leaves with short-rhombic marginal cells at the rounded-obtuse apex; GC, SW

Leaves with margins differing in color and/or opacity from the medial laminae.

Margin darker because 3-5 cell layers thick; plants blackish; on rocks in rivers; WC, NW

Margin paler and yellowish due to thick -walled, less papillose cells.

Leaves distinctly toothed above; basal membrane lacking ; 2* ; SE

Leaves entire; basal membrane present; 1*.

Peristome (32) spirally twisted above a high basal membrane; WS

Peristome (16) obliquely slanted above a low basal membrane; WS

Margin greener (cells thin -walled and less papillose) and spirally revolute; 1*; WC, SW

Leaves with an intramarginal "border", i.e., differentiated cells just inside short marginal cells.

"Border" of long, narrow, pellucid cells along leaf bases.

Basal cancellinae (hyaline, inflated cells) present; plants green; on soil; FL

Basal cancellinae lacking; plants blackish; on rocks in rivers; WC, NW

"Border" of enlarged, +isodiametric, yellow to orange, thick-walled cells. 1*; W

Group A19 - Leaves with distinct alar cells (Skeleton)

Stems tomentose; alar cells inflated, hyaline and +yellow-brown towards the margin; WS

Stems not or indistinctly tomentose; alar cells not as above.

Costa broad, >1/3 leaf width; alar cells inflated , and hyaline to brownish to reddish.

Costa 3(4) cell layers thick (middle layer green; external layers hyaline); N*

Costa lacking the above unique characters.

Inner basal cells pale, enlarged and extending up along the costa; N*

Inner basal cells little differentiated; WS

Costa narrow, <1/3 leaf width.

Alar cells enlarged to inflated and yellowish to brownish.

Capsules curved and strumose (goiter-like swellings); A/A

Capsules obovoid to pyriform; on rocks.

Capsules ribbed (dry); peristome teeth wide-flaring, +split and striolate; N

Capsules smooth (dry); peristome teeth erect, +entire and papillose; N*

Capsules cylindrical; substrates various.

Cells with cuticular ridges; peristome teeth +entire and papillose; N*

Cells smooth; peristome teeth forked and pitted-striolate below; WS

Alar cells sub-quadrate and pale; cells +thick -walled and often nodulose; WS

Group A20 - Leaves with costa extremely reduced to lacking (Skeleton)

Leaves in clusters of branches around a central stem and a network of green and hyaline cells; WS

Leaves distichous , decurrent and confluent ; protonemata luminous ; Goblin Gold ; WS*

Leaves complanate; cells pleuripapillose; on tree bark; GC

Leaves awned; cells smooth; on tree bark .

Leaves with conspicuous primordial utricles ; peristome lacking; TX

Leaves lacking utricles; peristome present; OK and TX

Leaves spinose serrate; protonemata persistent; cells smooth; pygmy ephemerals; WS

Leaves lacking the above unique characters.

Cells papillose; capsules exserted and valvate (4x); plants reddish-black; on rocks; N*

Cells smooth.

Capsules exserted with 4 prominent teeth; on undersides of rock overhangs; N

Capsules sessile and gymnostomous ; pygmy ephemerals; on soil; WS

Group A21 - Cells long (>5:1) and smooth (Skeleton)

Leaves flexuose-twisted (dry); cell walls +thickened ; capsules mostly erect; SA, CA

Leaves little altered (dry); cell walls not thickened; capsules inclined to pendulous; WS

Group A22 - Cells intermediate (2-5:1) and distinctly papillose (Skeleton)

Leaves broadly spathulate with rounded , crenulate apices; papillae C-shaped; FL

Leaves ovate and abruptly narrowed to a short acumen; papillae simple; W, VT

Leaves linear-lanceolate to subulate from an erect base; papillae simple; WS

Group A23 - Cells intermediate (2-5:1) and distinctly prorulose (Skeleton)

Leaves julaceous and 5-ranked ; peristome teeth fused at tip; A/A

Leaves and peristome teeth otherwise.

Setae flexuose; capsules symmetric and rugulose; peristome reduced; NC, TN

Setae straight; capsules asymmetric and furrowed; peristome teeth lanceolate.

Leaves with bistratose margins and/or lamina; mesic habitats; WS

Leaves unistratose; hydric habitats; WS

Setae short, capsules immersed.

Leaves +linear-lanceolate and +spinulose above; protonemata persistent; WS

Leaves +subulate and serrulate above; protonemata ephemeral; WS

Leaves predominantly broader near or above the middle (+oblong or obovate).

Plants small, winter annuals on soil.

Capsules clearly exserted.

Costa strong; protonemata ephemeral ; peristome lacking; WS

Costa weak; protonemata persistent ; peristome present; WS*

Capsules +immersed and +pyriform .

Leaves +concave-obovate and serrulate; capsules operculate; WS

Leaves +concave-ovate and entire; capsules cleistocarpous; WS

Plants otherwise .

Leaves with an obtuse apex bordered with short -rhombic cells; GC, SW

Leaves commonly bordered by linear cells; capsules pyriform and pendent; WS

Leaves unbordered.

Medial cells strongly bulging on both sides; AK

Medial cells smooth and >5:1 (linear rhomboidal); capsules pendent; WS

Medial cells smooth and <4:1 ; capsules inclined to erect.

Peristome of 4 massive teeth; plants bud-like ; costa weak; on rocks; N

Peristome of 16 teeth; costa strong; on soil.

Capsules with well-differentiated necks; calyptrae mitrate; N*

Capsules lacking a distinctive neck; calyptrae inflated cucullate.

Capsules inclined and asymmetric; WS

Capsules erect and symmetric ; WS

Peristome lacking; capsules erect and symmetric; calyptrae mitrate; WS

Leaves predominantly broader near the base (+lanceolate).

Plants small, winter annuals on soil; capsules +immersed and cleistocarpous; WS

Plants otherwise; capsules exserted and peristomate.

Leaves +subulate / setaceous.

Capsules ovoid; plants minute to very small; on calcareous rocks; WS (N)

Capsules long cylindric; peristome teeth round, fully split and papillose; WS

Capsules +oblong, often curved ; peristome teeth flat , split 1/2 and pitted; WS

Leaves flexuose-twisted (dry); cells +thick-walled; SA, WC

Leaves with expanded, sheathing leaf bases; WS

Leaves lacking any of the above unique characteristics.

Leaves >1mm; capsules terminal.

Costa percurrent; capsules erect; peristome single.

Upper cells +linear; peristome teeth long & split; WS

Upper cells broad; peristome teeth short & irregular; N

Costa subpercurrent; capsules +pendant; peristome double; WS

Leaves <1mm; capsules lateral; peristome single; on Cu or S rich soils; N*

^# Note - cells bulging, mammillose (both bulging and papillose) or indistinctly papillose, i.e., low papillae.

Group A25 - Cells short (<2:1) and distinctly papillose (Skeleton)

Leaves with expanded , sheathing bases; cells strongly bulging on upper surface; WS

Leaves distinctly toothed in the upper half.

Cells pleuripapillose ; leaves +squarrose -recurved; 2*.

Leaf lamina +bistratose; stem hyalodermis present; peristome lacking; SW

Leaf lamina unistratose; stem hyalodermis lacking; peristome present; SE

Cells unipapillose or mammillose; ventral stereid band weak or lacking.

Leaves +broad; cells mammillose; capsules smooth; WS

Leaves +narrow; cells coarsely papillose; capsules furrowed; N

Leaves with large, curved, projecting papillae at extreme apex; cells mammillose: NW

Leaves ligulate and rounded-obtuse ; cells pleuripapillose ; 0* ; WS*

Leaves with revolute margins and smoother , greener marginal cells; 1* ; WC, SW

Leaves lacking the above unique characteristics.

Cells collenchymatous and stellate; 2* .

Leaves squarrose -recurved (wet); cells pleuripapillose; A/A

Leaves +erect (wet); cells unipapillose; A/A

Cells pleuripapillose; but neither collenchymatous nor stellate.

Papillae flower-like (massive and multifid); peristome lacking; 2* ; SE

Papillae forked; basal cells with brown cross-walls; calyptrae long-cylindric; WS

Papillae C-shaped.

Basal cells with brown cross-walls; calyptrae long-cylindric; 1*; WS

Basal cell walls uncolored; calyptrae cucullate.

Peristome teeth long and twisted; 2* ; WS

Peristome teeth short and erect; 1* ; WS

Papillae conical.

Cells with 4-7 papillae; peristome reduced to lacking.

Stems repeatedly forked; capsules elongate and urn-shaped; 2 *; WS

Stems sparsely forked; capsules +pyriform; 1 * or lacking; WS*

Cells with 1-4 papillae.

Costa with two stereid bands.

Leaf margins revolute on both sides; peristome present.

Papillae crowded; basal cells hyaline; peristome twisted; WS

Papillae scattered; basal cells green; peristome +oblique; WS

Leaf margins revolute on one side only; peristome lacking; WS

Leaf margins plane; peristome lacking .

Leaves >2 mm; sporophytes lateral; A/A

Leaves <2 mm; sporophytes terminal; WS

Costa with one stereid band; peristome lacking.

Sporophytes lateral; stem rounded-triangular; WS

Sporophytes terminal; stem round ; WS

Costa lacking stereid bands; peristome present.

Basal marginal cells with thickened cross-walls; WS

Basal marginal cells +undifferentiated; WS

Cells unipapillose; but neither collenchymatous nor stellate.

Leaves serrulate at apex; stems tomentose; gemmae on stem extensions; WS

Leaves entire.

Capsules exserted; peristome of 32 twisted teeth ; plants on soil and rocks; 2*; WS

Capsules +emergent and valvate (4x); blackish plants on rocks; 0* ; N*

Capsules +immersed with 16 +reflexed teeth; plants on trees and rocks; 0* .

Basal marginal cells with thickened cross-walls; WS

Basal marginal cells +undifferentiated; WS

Group A26 - Cells short (<2:1) and smooth (or indistinctly ornamented#) (Skeleton)

Leaves +obovate (broadest in upper third; shaped like an upside-down egg), concave and broadly obtuse; 1* .

Leaves cucullate; costa subpercurrent; TX

Leaves muticous to piliferous; costa subpercurrent to excurrent; NW

Leaves +oblong-spathulate (broad in the middle and even broader above).

Leaf margins inrolled when dry (erect or plane when wet); cells bulging on upper surface.

Leaves 1.5 -3 mm and +toothed above; peristome lacking; 2*; E

Leaves 1 -2 mm and +entire above; peristome present; 1*; FL, GA

Leaf margins usually revolute, at least in part; cells flat.

Leaves +bordered with longer cells; peristome teeth short and erect; 1* ; WS

Leaves +bordered with shorter cells; peristome teeth long and twisted; 1* ; WS

Leaves with intra -marginal border of enlarged, thick -walled , orange cells; 1* ; W

Leaves unbordered.

Propagula on basal leaf surfaces ; sporophytes unknown; 1*; SE

Propagula axillary; peristome of 32 spirally twisted teeth; 2* ; WS

Leaf margins plane; cells flat and large (> 15µ); peristome none or rudimentary; 1* ; WS

Leaves +oblong-lingulate (tongue-shaped)or oblong-ligulate (strap-shaped).

Leaves +lingulate; cells 2(3)stratose; awns on perichaetial leaves; capsules sessile; E, BC

Leaves +ligulate ; cells unistratose; perichaetial leaves +acute; capsules exserted.

Leaves acute; capsules gymnostomous (lacking a peristome); 1* ; WS

Leaves obtuse; capsules peristomate (peristome present); 0*; WS*

Leaves +ovate (broadest in lower third; egg-shaped) and revolute; peristome of 32 teeth; 2*; WS

Leaves ovate-lanceolate to lanceolate (broadest near the base; lance-shaped).

Leaves 3-ranked; setae very long; plants of calcareous wetlands; N

Leaves falcate -secund ; capsules valvate ; plants saxicolous and blackish; NW

Leaves with expanded, sheathing leaf bases.

Cells bulging on upper surface; capsules symmetric and oblong -ovoid; WS

Cells smooth; capsules asymmetric and strumose (goiter-like swelling); WS

Leaves with paired teeth on bistratose margins.

Margins revolute below; cells with cuticular ridges; perichaetia terminal; N*

Margins plane; cells smooth; perichaetia lateral (basal); GC

Leaves with an intramarginal band of long, narrow cells at base; WC and NW

Leaves bistratose, at least in part.

Leaf cells strongly bulging on upper surface & unistratose at margins; 2*; WC, SW, TX

Leaf cells smooth to +bulging/papillose & bistratose at margins.

Leaf margins erect/involute; calyptrae mitrate, lobed and plicate; 2* ; WS

Leaf margins plane; calyptrae cucullate, entire and smooth; 1* ; WC, AZ

Leaves lacking any of the above unique characters.

Capsules split along 4 sutures; plants saxicolous and blackish; N*

Capsules with 4, massive teeth; leaves pellucid ; terminal gemmae cups; WS

Capsules with 8, 16 or 32 lanceolate teeth.

Plants in tufts on tree trunks (rarely on rocks); diplolepideous.

Leaves crisped when dry; basal cells yellow, thick -walled; WC

Leaves not crisped when dry; basal cells +undifferentiated; WS*

Plants in tufts, cushions or mats on rocks.

Peristomes diplolepideous (double).

Basal cells very thick -walled, yellow and radiating from costa; WS

Basal cells +thick -walled, neither yellow and nor radiating; WS

Peristomes haplolepideous (single).

Plants very small (<2 mm); setae cygneous (wet); N

Plants larger (>2 mm).

Capsules systylious; calyptrae short; in wetter habitats; WS

Capsules not systylious; calyptrae longer; in dryer habitats; WS

Plants on soil primarily.

Setae cygneous.

Capsules yellow-orange with red ribs; calyptrae cucullate; A/A

Capsules yellowish and smooth; calyptrae mitrate; N*

Setae bent at capsule base; capsules curved, sulcate, +strumose & purple-red (yellow); leaves revolute

+throughout & serrate apically; upper cells +square; WS

Setae straight.

Capsules ribbed; in crevices of cliffs and boulders.

Peristome teeth divided to half their length; N

Peristome teeth undivided; basal cells hyaline; E

Capsules smooth (or wrinkled when dry).

Setae very long; capsules inclined; peristome double; in fens; N

Setae shorter; capsules erect; peristome single; on mineral soils.

Basal cells hyaline; peristome teeth twisted; WS

Basal cells green; peristome teeth +oblique; WS

^# Note - cells bulging, mammillose (both bulging and papillose) or indistinctly papillose, i.e., low papillae.

Cells = medial, laminal cells; cells ~2/3 of the way from insertion to apex, midway between the costa and the margin.

Cell length to breadth ratio:

Long cells: >5:1; commonly termed linear.

Intermediate cells: 2-5:1; commonly termed elongated, rectangular, hexagonal, or rhomboidal.

Short cells: <2:1; commonly termed isodiametric, quadrate, rounded-quadrate, or sub-quadrate.

Number of stereid bands evident in costa cross-sections:

2* = costa with two stereid bands

1* = costa with one stereid band

0* = costa lacking stereid bands, i.e., +homogeneous